/*
 * #!
 * Ontopia DB2TM
 * #-
 * Copyright (C) 2001 - 2013 The Ontopia Project
 * #-
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * !#
 */

package net.ontopia.topicmaps.db2tm;

/**
 * INTERNAL: A change log reader is a tuple reader that is used to
 * read a change log relation. For each tuple read it also returns the
 * type of change and an order value that says something about the
 * order in which the change occurred.
 */
public interface ChangelogReaderIF extends TupleReaderIF {

  /**
   * INTERNAL: Returns the type of change that the current tuple went
   * through.
   */
  ChangeType getChangeType();

  /**
   * INTERNAL: Returns the current order value found in the
   * order-column. This information is used so that one can keep track
   * of incremental updates.
   */
  String getOrderValue();
  
}
